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CVE-2021-30481 is a buffer overflow vulnerability in Valve Steam, affecting installations with a Source engine game through 2021-04-10. The vulnerability is triggered when a remote authenticated user sends a specially crafted Steam invite, which, after a single click by the victim, causes a buffer overflow, allowing the attacker to execute arbitrary code on the victim's system.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
This repository contains an exploit for CVE-2021-30481, a vulnerability in the Valve Steam Client's RCON handler. The main exploit logic is implemented in 'exploit.py', which sets up a malicious RCON server and uses the SteamworksPy library to invite a victim (by Steam ID) to connect. Upon connection, the exploit abuses the screenshot response handler to deliver a crafted zip file containing a malicious executable, which is saved as 'csgo/screenshot0000.jpg' on the victim's machine. The exploit can then trigger the execution of this file, either running a default payload (calc.exe) or a custom binary provided by the attacker. The shellcode for execution is provided in 'shellcode.asm' and embedded in the Python script. The exploit requires the attacker to know the victim's Steam ID and to use their public IP address for the RCON connection. The repository structure is straightforward: 'exploit.py' (main exploit logic), 'shellcode.asm' (assembly shellcode), and 'README.md' (basic usage and CVE reference).
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